Home humidity level

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Hi all

Might have seen my earlier post about my house a/c not cooling that well. Now I'm having an issue with humidity. The house is currently at 63% humidity and the a/c has been running on and off all day. From a quick google search this is way too high. The a/c system should be removing the humidity but it doesn't appear to be doing so.

Aside from getting a dehumidifier I'm not sure what to do....
 
Who says that is too high? Doesn't that depend upon ambient temperature and total ambient humidity level?

If it's 75 out and you're setting the home to 72, and it's really humid out, an oversized AC system will not run long enough to dehumidify before cutting out on temp.
 
When the AC guys work on my unit, they take the ambient temperature and then stick a temperature probe into the flexible "fabric" on top of the AC unit in the house and look for an airside 20°F delta.

Make sure your unit outside condenser unit is clean so it's efficient. Look for ice build up on the coil inside your house inside the "furnace".
 
What is the humidity outside? Is it raining today? If it is, you can't expect the humidity to be back to 50%.
Did you verify with another humidity meter? (They are about $10 at hardware store).

Where is the humidity coming from if you're higher than outside...esp. with the a/c running which itself is basically working as a dehumidifier itself. Are you exhausting the A/C back in the house?
 
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is it always 85% or is it a one day thing because it's raining. I think you only need to freak out if this is a consistent thing, versus a couple days here and there
 
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Originally Posted By: raytseng
is it always 85% or is it a one day thing because it's raining


It's been raining on and off and it's supposed to rain tonight. Even though I've lived in Ohio my entire life, I cannot speak to the average humidity but I do feel that it is currently higher than normal.

I did have the attic access panel (has one of the fold down ladders) sealed off with plastic, not sure if that has anything to do with it but I removed it a bit ago.

The A/C unit was, according to the tech, severely low on refrigarant when it was serviced last August...not sure if it's all leaked out again...or if that would even have a real effect on humidity.

If you can't tell already, I know absolutely nothing about HVAC.
 
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how long does the system run? 50% seems reasonable if the temp is holding what you have it set at.
 
Check the temp difference between the output from the vents vs the the return duct. Should be a 15 to 20 degree difference.
 
Originally Posted By: Throt
If you can't tell already, I know absolutely nothing about HVAC.


Then you need to find a qualified professional.

Humidity levels should be kept below about 55%, with ideal being about 45%. Too high and you start to have issues with mold, staining, and other moisture related damage. Too low and it can cause issues with wood flooring, dry sinuses, and dry skin issues. Keep an eye on basements-especially in older homes, too much humidity can cause moisture issues that can be felt and smelled in the rest of the house.

Even in wet weather, a well designed home with a well designed HVAC system will keep the humidity consistent throughout the house during the humid weather (including below ground level). The same system will be able to maintain humidity levels in dry winter months. To offer good advice requires more expertise than is available on any discussion forum.
 
Originally Posted By: JHZR2


If it's 75 out and you're setting the home to 72, and it's really humid out, an oversized AC system will not run long enough to dehumidify before cutting out on temp.


+1

oversized is not better.
 
My preferred humidity and temperature are no more than 50% at 68°F. Right now I'm at 45% at 71, which is just fine.
 
Current temp outside is 73 w/ 86% humidity. Inside temp is 72 and 66% humidity. Air has been running on and off all morning.

Ugh.
 
How many square feei it your house and How many ton's of A/C do you have?

Contractors typically oversize A/C by 30%+ so that there will be no call backs. As a result the A/C doesn run long enough to de-humidify.

When you have say a 2500 - 3000 sq ft house typically you will have 3 1/2+ Ton unit when 2 1/2 would be much better.

Bigger is not better.
 
Home is 1,690 sq. ft. 1 story, brick. Decent windows. Most are still sealed from the winter with that plastic you use a hair drier on.

Here is a pic of our unit specs.

218EB994-3F7B-4981-AB5A-4F69EC38EE1F_zpsw5oben65.jpg
 
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Really? A smart guy like you buys an overpriced dehumidifier hawked by Willie Nelson?!?

Just the fact that it says "water from air" makes me want to run and scream.

Originally Posted By: Shannow
I've got one of these units (the one Willie Nelson is leaning on)

http://www.dailykos.com/story/2008/04/21/499240/-Creating-Drinking-Water-From-Air#

Makes great drinking water, but I haven't run it in ages, as it uses a bunch of 27c/KWHr electricity....maybe when I get rooftop solar I'll fire it up again.
 
That's a 2.5 ton compressor, pretty close to right sized for Ohio.

What kind of bathroom ventilation do you have? A good exhaust fan that you run during and for 15 minutes after a shower will help with the indoor humidity.
 
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